Abstract
BACKGROUND: Webtag is a tool providing oligonucleotide sequences (usually called tags or anchors) that are absent from a specified genome. These tags/anchors can be appended to gene specific primers for reverse transcriptase polymerase chain reaction experiments, circumventing genomic DNA contamination. RESULTS: The use of a relational database, in conjunction with a series of scripts written in PHP and Perl, allows the user to rapidly obtain tags that are: 1) suitable for a specific organism, and 2) compatible with other oligonucleotides to be used in the experimental procedures. CONCLUSION: This new web tool allows scientists to easily and rapidly obtain suitable tags for RT-PCR experiments, and is available at http://www.egs.uu.se/software/webtag/.